Royal H. Frost discovered IC 4599 = F. 1144 on a plate taken on 20 Jun 1903 with the 24-inch Bruce photographic refractor at Harvard's Arequipa station. He noted "Planetary, magn. about 15." Kohoutek's "Catalogue of Galactic Planetary Nebulae" (CGPN) doesn't label PK 338+5.1 as IC 4599.

300/350mm - 13.1" (3/17/86): at 79x appears as an out of focus star with an estimated V magnitude of 12.5-13.0. Considerable contrast gain with an OIII filter. Forms the northern vertex of a triangle with a mag 11 star 2.5' SSW and a mag 10 star 2.7' SE. The planetary appears fainter than the two stars unfiltered but much brighter with a filter. A small disc is clearly visible at 166x or higher. Identified as He 2-155 in CGPN and ESO-Strausberg catalogues.

Notes by Steve Gottlieb